Before attempting to dismount a filesystem, it must be inactive. If "any user" has one
of the filesystem's directories as their current directory or has any file within the
filesystem open, you will receive an error message, like the one below, when attempting
to unmount the filesystem:

# umount /dev/dsk/c0t2d0s7
umount: /dev/dsk/c0t2d0s7: device is busy

Well, the fuser command to the rescue. The fuser command may be
used to determine which files or directories within a filesystem are currently in use
and to identify the processes and users that are using them. fuser is available
on all major flavors of UNIX with the exception of Digital UNIX.

The fuser command can take two types of arguments:

normal filename: You can pass a normal filename or directory to the fuser
command. In this case, it reports on that file or directory alone.

special disk: You can also pass in a special disk name as an argument to
fuser. In this case, it reports on all files and directories within the
corresponding filesystem.

You can use the -u option to the fuser statement to display the user ID's
as well as PID's in its output.

Lets look at a few examples. The following command will display all processes and their
associated users that are using files/directories on a specified disk on a Sun Solaris
system:

In the above example, there are two processes using the filesystem mounted on
/dev/dsk/c0t2d0s7 (which in my example is the /db filesystem) at the
time of running the command. The User ID's are root, and oracle. The c
being printed after the PIDs indicate that this is their current directory.

You can use the -k option to kill all processes using the specified
file or filesystem. In the following example, the UNIX PIDs 1313 and 1223 will be
killed:

# fuser -k /dev/dsk/c0t2d0s7
/dev/dsk/c0t2d0s7: 1313co 1223c

In Linux, you can use the -m option to allow you to specify
the filesystem by name. On Solaris and IRIX, the -c option
performs the same task.

--- end article ---

Last modified: 07/05/2006
(most likely earlier as a site migration in 2006 reset some dates)
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This website is a personal resource. Nothing here is guaranteed correct or complete, so use at your own risk and try not to delete the Internet. -Stephan